This invention relates to an oil supply system for a vertical engine, and more particularly, to an improved lubricating system for an outboard motor.
Although two-cycle internal combustion engines are widely employed as the power plants for outboard motors, there is an interest in the application of four-cycle engines for this purpose. The application of a four-cycle engine to an outboard motor presents certain peculiar difficulties. These are caused by the fact that the engine is normally positioned so that its crankshaft rotates about a vertically extending rather than a horizontally extending axis. In addition, it is necessary to provide a lubricant sump and lubricating system for such engines allowing their vertical orientation. In addition, there is the always present difficulty of locating all of the necessary components of the engine in a manner so that those components which require servicing can be easily accessed. The oil filter of such an engine is an element that should be readily accessible, as it is desirable to change the oil filter at frequent or at least regular intervals.
In conjunction with four-cycle engine application for outboard motors, it has been the normal practice to position the oil filter on one side of the cylinder block. However, there are a number of other engine auxiliaries, such as the induction system, exhaust system and ignition system, that are also so located, and this gives rise to problems in ensuring that all components can be easily serviced and yet that the components will not interfere with each other.
Also, it is generally desirable to provide some of the servicing on the outboard motor on the motor while it is still attached to the transom of an associated watercraft. This presents additional difficulties in the location of the various components which should be serviced frequently, or at least regularly.
It is, therefore, a principal object of this invention to provide an improved lubricating system for an outboard motor.
It is another object of this invention to provide an improved lubricating system for an outboard motor embodying a four-stroke internal combustion engine.
It is a yet further object of this invention to provide an improved and simplified oil filter location for such outboard motors in which the oil filter is readily accessible for servicing.